air conditioning musty smell

Anyone have any advice about my cars air conditioning system? When I first turn it on I get a musty smell that soon dissipates, what could be the problem? The dealer says this is normal, but I don't know about that. I tried running with A button in various positions but it didn't help. I have a 2002 325i.

Interesting that the smell doesn't stay but dissapates. Check around the intakes for the A/C system, maybe some mold or leaves or something else in there. Not really sure where this is on the E46. Maybe consult a repair manual from your local Autozone\Pep boys. How many miles are on the car? If it's still really new, it might just be breaking itself in and the smell may go away after more milage.

The smell is there most likely because the AC system is run on recirc often. It creates a mildew smell because of no fresh air to rid the moisture. Find some lysol or febreeze. Pop you hood, and in the back of the engine compartment you will see a long panel that follows the windshield. On this panel you will see three clips, one in the middle and one on each end. Turn these clips 90* Lift up on the panel and pull it towards you. You will now see a filter. It wouldn't hurt to change that either. Anyway, spray the febreeze or lysol into the vent area where the microfilter covered. Make sure you have the ac on so it sucks it in to the proper areas. Spray it a couple of times and you should be good. Just keep alternating between recirc and fresh air. Hope this helps

Thanks for the above info, I appreciate it, and i'll give it a try.

the musty smell is from mildew that builds on your micro filter. change this and you wil be ok. the filetr is under the dash, accessable by removing the glove box. it is positioned in the centre of the dash. if you have a convertible.,.... remove it, , no need to have a filetr on convertible.:)

Ok nut, the micro filter on an e46 is under the hood. The micro filter for your car, e36 is under the dash and you don't have to remove the glove box, just remove the panel under the glove box and you will see the cover for it once you move the junction panel that is in the way.